1. Field of the Invention
The present invention relates to a printing apparatus, a method for controlling the printing apparatus, and a storage medium.
2. Description of the Related Art
Conventionally, a printing apparatus includes a plurality of sheet storage units and conveys a sheet from one of the sheet storage units for printing an image on the conveyed sheet.
Some of these printing apparatuses have an automatic sheet selection function. The automatic sheet selection function refers to a function that finds a sheet storage unit which stores sheets of desired size for printing from among the sheet storage units and selects the found sheet storage unit as a sheet storage unit to be used for printing. For example, Japanese Patent Application Laid-Open No. 11-301047 discusses a printing apparatus which assigns priority to each of a plurality of sheet storage units, and the printing apparatus checks the sheet storage units, beginning with the highest-priority sheet storage unit, to determine whether sheets of a desired size for printing are stored.
Such a printing apparatus conveys a sheet from a sheet storage unit selected by the automatic sheet selection function, and prints an image on the conveyed sheet.
A sheet conveyance distance from a plurality of sheet storage units to an image forming unit of a print engine varies according to the respective sheet storage units. For higher printing productivity, a conventional printing apparatus preferentially selects a sheet storage unit nearer to the image forming unit.
Conventional sheet storage units are classified into two types. One type of sheet storage unit includes a sensor that can detect the size of stored sheets, and the other type of sheet storage unit cannot detect the size of stored sheets. Each type of sheet storage unit has advantages and disadvantages.
A sheet storage unit that can detect the size of stored sheets detects the size of a sheet by the sensor and eliminates the need for a user to specify the size of sheets that are set in the sheet storage unit. However, an additional cost is required for installation of the sensor in the printing apparatus.
On the other hand, a sheet storage unit that cannot detect the size of stored sheets requires the user to manually specify the size of sheets that are set in the sheet storage unit. However, the cost of the printing apparatus can be kept low since there is no need for installing the sensor.
Some printing apparatuses include both of the two types of sheet storage units described above.
For example, one is a sheet storage unit originally equipped in the printing apparatus and includes no sensor therein, and the other is a sheet storage unit which is added as an optional device and includes a sensor for detecting the size of a sheet.
In such a printing apparatus, the originally equipped sheet storage unit is nearer to the image forming unit. This means that the automatic sheet selection function preferentially selects the sheet storage unit which cannot detect the size of stored sheets as a sheet storage unit to be used for printing. However, because a user manually specifies size information for a sheet storage unit that cannot detect the size of stored sheets, the user may sometimes make a mistake in setting the information. A mismatch between the size information set to the sheet storage unit and the size of an actually stored sheet produces an unintended print result such as an occurrence of an image defect or printing of a smaller image in relation to the size of the sheet.
One possible solution to this issue is to make a setting to remove the sheet storage unit which cannot detect the size of stored sheets from a selectable target of the automatic sheet selection function. However, such a setting reduces the number of selectable targets by the automatic sheet selection function, and may increase a possibility that printing will stop because no sheet for printing is found.